Saw.



No. 720,313. PATENTED FEB. 10, 1903. R.-H. BENNER.

SAW.

APPLICATION FILED JUNE 27. 1902.

H0 MODEL.

. UNITED th rns PATENT .FFHCE.

REUBEN H. BENNER, OF CINCINNATI, OHIO.

SAW.

SPECIFICATION forming part of Letters Patent No. 720,313, dated February10, 1903.

Application filed June 27, 1902. Serial No. 113,543. (No model.)

To all whom it may concern.-

Be it known that I, REUB N H. BENNER, a citizen of the United States ofAmerica, and a resident of Cincinnati, in the county of Hamilton andState of Ohio, have invented certain new and usefulIm provements inSaws, of which the following is a specification.

This invention relates to certain improvements in saws, and particularlyto the saws of circular sawing machines, and has for its object toprovide a saw of an improved and simple construction by means of whichthe thinner and toothed edge portion of the saw is strengthened andprotected against lateral or side strains, so that the saw is caused toproduce a straight kerf and bending or cracking of the saw is prevented.

The invention consists in certain novel features of the construction,combination, and arrangement of the several parts of the improved saw,whereby certain important ad-' vantages are attained and the device ismade simpler, cheaper, and otherwise better adapted and more convenientfor use than various other forms of circular saw heretofore devised, allas Will be hereinafter fully set forth.

The novel features of the invention will be carefully defined in theclaims.

In order that myimprovements may be the better understood, I haveillustrated in the accompanying drawings a segmental circular sawconstructed according to my invention,

I in which drawings- Figure 1 is a side elevation of the saw, showingthe improvements applied thereto; and

Fig. 2 is a sectional view drawn to an enlarged scale and taken throughone edge portion of the saw in the plane indicated by the dotted line aain Fig. 1. Fig. 3 is a sectional View similar to Fig. 2, but takenthrough the edge portion of the saw in the plane indicated by the dottedline b b in Fig. 1.

As shown in the views, the saw to which my improvements are applied isof the segmental circular type and is constructed with a central collaror hub 1, adapted to be secured upon a saw shaft or arbor in anyordinary way, and provided with an annular projection or flange 2,extended around its edge portion and gradually reduced in thickness fromsaid central hub or collar 1 toward its outer edge. The edge portion ofthe flange or projection 2 is provided upon one face of the saw with anannular recess extended around it and adapted to receive the inner ments3 3, the outer edges of which are curved concentrically with the sawshai'tor arbor and are provided with teeth or serrations 5 5, whereofthe cutting edge of the saw is formed.

The inner thickened end portions of the toothed segments 3 3 are formedwith openings 7 7 for the passage of screws whereby said segments aresecurely held upon the flange 2 of the hub or collar 1 of the saw withtheir toothed edges projecting beyond said flange, and said toothed edgeportions 5 of the segments 3 are made of less thickness than the innerthickened end portions of the segments, the said segments being madegrad ually increasing in thickness from their outer toothed edgeportions 5 toward their inner thickened portions 4, as indicated in Fig.2 of the drawings. The opposite side surfaces of the segments 3 betweenthe thinner outer edge portions 5 and the thicker inner portions 4 arecommonly made concaved, as indicated at 6 6 on the drawings.

The segments 3 have opposite edge portions 3 3, which are extended indirections parallel with radii of the saw, and in the attachment of thesegments to the flange 2 of the hub or collar 1 the said edges 3 3 ofeach two adjacent segments are spaced apart, so as to produce betweenthem an opening 3 also extended radially of the saw, in which opening isarranged a reinforcing part or piece 8, one end portion 10 of which ismade of athickness equal to that of the thickened inner portions 4 ofthe segments and is, similarly to said portions of the segments,provided with openings 11 for the passage of screws whereby thereinforcing part or piece 8 is held securely upon the recessed edgeportion of the flange 2 of the hub of the saw. As shown in Fig. 1, thereis such a reinforcing part or piece 8 arranged between the adjacentedges of each two adjacent segments 3 of the saw.

The length of the radially-extended reinforcing pieces or parts Sis lessthan the width, measured radially upon the saw,of the toothed segments 33, so that the outer ends 9 of said reinforcing pieces or parts arelocated inside thickened end portions 4 4 of a series of segof thetoothed outer edge portions 5 of the segments, and said outer ends ofthe reinforcing pieces or parts 8 are made of a thickness greater thanthe thickness of the portions of the segments 3 between which they arearranged, so that the opposite sides of the reinforcing pieces orpartsare caused to project outside of and beyond the opposite side surfacesof the segments, as shown in Figs. 2 and 3. The said outer ends 9 of thereinforcing pieces or parts 8 are, however, made of a thickness lessthan that of their inner end portions 10, and the side surfaces of theparts or pieces 8 between said outer and inner end portions 9 and 10 aremade tapered, so as to give to the reinforcing pieces or parts a generalwedge shape in cross-section. The side surfaces 12 of the reinforcingpieces or parts are preferably made plane, and by reason of theconcavities of the sides of the segments said side portions 12 of theparts or pieces 8 are caused to protrude from the concave side surfacesof the segments at substantially all points between the outer and innerend portions 9 and 10 of the pieces or parts 8, as clearly shown in Fig.2. The thickness of the outer end portions 9 of the reinforcing piecesor parts will preferably be but slightly greater than the thickness ofthe portions of the segments between which said pieces or parts areheld, so that at said outer ends the side portions of the said parts orpieces will protrude but little beyond the sides of the segments, andconsequently will offer but little resistance to the passage of the sawthrough the wood.

In the operation of the saw constructed according to my invention as thethinner toothed edge portion of the saw passes through the wood insawing the outer ends of the wedge-shaped reinforcing pieces or parts 8will be inserted in the kerf cut by said toothed edge portion and willactin the manner of wedges to force or spread the kerf open and permitthe teeth of the saw to clear, so that a very considerable part of thestress which would otherwise be borne by the thinner outer portion ofthe saw is relieved and is carried by the thicker, and consequentlystronger, wedge-shaped reinforcing parts or pieces, whereby cracking orother damage to the segments is prevented and the cost of maintainingand repairing the saw is considcrably lessened.

As the thin edge portion of the saw is capable of being very easily bentor deflected laterally or sidewise in cutting, it is evident also thatit will be materially strengthened and stiffened by the insertion of thereinforcing pieces or parts between the segments, so that it is enabledto withstand side strains such as are caused by lateral movements of thematerial being sawed, and in this way the sawed material is produced ineven and uniform thickness from end to end and is not liable to vary inthickness, as is the case where no such stiffening means are provided.This strengthening or stifiening of the saw also serves to materiallylessen the liability to damage or bending of the saw caused by suchlateral movement of the materials being sawed and in this way also tendsto lessen the cost of repairs. By reason also of the stiffening orstrengthening of the thinner edge portions of the saw by means of theinserted reinforcing devices it will be evident that the outer cuttingedges of the saw may be made in a thickness less than is necessary inother constructions, so that the kerf taken out by the saw is lessenedand the allowance for out is reduced, whereby a considerable saving inmaterial is effected.

From the above description of myimprovements it will be seen that thesaw constructed in accordance with my invention is of an extremelysimple and inexpensive nature and is especially well adapted for thepurposes for which it is designed, and it will also be evident from theabove description that the device is capable of some modificationwithout material departure from the principles and spirit of theinvention, and for this reason I do not wish to be understood aslimiting myself to the precise form and arrangement of the several partsof the device as herein set forth.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

l. A saw having its blade provided with transversely-extendedreinforcing parts or pieces extended beyond the side surfaces of the sawand adapted for contact with the material being sawed to relieve strainsupon the blade, substantially as set forth.

2. A saw having its blade provided with transversely-extendedreinforcing parts or pieces the opposite side portions of which areextended beyond the side surfaces of the saw and are adapted for contactwith materials being sawed to relieve strains upon the blade,substantially as set forth.

3. A saw having its blade provided with transversely-extendedreinforcing parts or pieces of wedge shape in cross-section, theopposite side portions of said parts or pieces being extended beyond theside surfaces of the saw and being adapted for contact with materialsbeing sawed to relieve strains upon the saw, substantially as set forth.

4. A saw having openings produced in it and provided with reinforcingparts or pieces arranged in said openings with side portions extendedout beyond the side surfaces of the saw and adapted for contact withmaterials being sawed to relieve strains upon the blade, substantiallyas set forth.

5. A saw having openings produced in it and provided with reinforcingparts or pieces arranged in said openings and made in wedge shape withinclined side portions extended out from said openings and beyond theside surfaces of the saw for engagement with materials being sawed torelieve strains upon the ing inclined side portions extended out fromthe openings and beyond the side surfaces of the segments in positionfor engagement'with materials being sawed to relieve strains upon 1 5the segments, substantially as set forth.

Signed at Cincinnati, Ohio, this 23d day of June, 1902. I REUBEN H.BENNER. Witnesses:

JOHN ELIAS JONES,

L. M. JONES.

